Red Hat Single Sign-On 7.6

A misconfiguration flaw was found in Keycloak. This issue can allow an attacker to redirect users to an arbitrary URL if a 'Valid Redirect URI' is set to http://localhost or http://127.0.0.1, enabling sensitive information such as authorization codes to be exposed to the attacker, potentially leading to session hijacking.

Published: 2024-09-19T15:48:28.468Z
Updated: 2026-04-01T13:27:25.248Z

A vulnerability was found in Undertow. This vulnerability impacts a server that supports the wildfly-http-client protocol. Whenever a malicious user opens and closes a connection with the HTTP port of the server and then closes the connection immediately, the server will end with both memory and open file limits exhausted at some point, depending on the amount of memory available. At HTTP upgrade to remoting, the WriteTimeoutStreamSinkConduit leaks connections if RemotingConnection is closed by Remoting ServerConnectionOpenListener. Because the remoting connection originates in Undertow as part of the HTTP upgrade, there is an external layer to the remoting connection. This connection is unaware of the outermost layer when closing the connection during the connection opening procedure. Hence, the Undertow WriteTimeoutStreamSinkConduit is not notified of the closed connection in this scenario. Because WriteTimeoutStreamSinkConduit creates a timeout task, the whole dependency tree leaks via that task, which is added to XNIO WorkerThread. So, the workerThread points to the Undertow conduit, which contains the connections and causes the leak.

Published: 2024-02-19T21:23:14.496Z
Updated: 2026-06-10T08:35:37.476Z

A flaw was found in Keycloak, where it does not properly validate URLs included in a redirect. This issue could allow an attacker to construct a malicious request to bypass validation and access other URLs and sensitive information within the domain or conduct further attacks. This flaw affects any client that utilizes a wildcard in the Valid Redirect URIs field, and requires user interaction within the malicious URL.

Published: 2024-04-17T13:21:19.130Z
Updated: 2026-05-16T23:26:21.991Z

An unconstrained memory consumption vulnerability was discovered in Keycloak. It can be triggered in environments which have millions of offline tokens (> 500,000 users with each having at least 2 saved sessions). If an attacker creates two or more user sessions and then open the "consents" tab of the admin User Interface, the UI attempts to load a huge number of offline client sessions leading to excessive memory and CPU consumption which could potentially crash the entire system.

Published: 2023-12-14T18:01:26.005Z
Updated: 2025-11-11T15:10:51.908Z

A flaw was found in the redirect_uri validation logic in Keycloak. This issue may allow a bypass of otherwise explicitly allowed hosts. A successful attack may lead to an access token being stolen, making it possible for the attacker to impersonate other users.

Published: 2024-01-26T14:23:43.185Z
Updated: 2025-11-11T16:12:14.005Z